The present invention relates to a new and improved construction of an apparatus for the continuous winding-up or winding-off or unwinding of substantially flat or superficial structures or products into a package or from a package, respectively.
Generally speaking, the apparatus of the present development for the continuous winding-up or unwinding of substantially flat or superficial structures or products, especially, although not exclusively, printed products, in an imbricated or shingled formation, into a package or product package or from a package or product package, respectively, is of the type comprising a driven winding core member which can be elevationally displaced or shifted in position There is also provided a supply spool member for a winding band or tape, sometimes also referred to in the art as a winding strap, which is reeled or wound-up in conjunction with the substantially flat structures or unreeled or unwound in conjunction with the substantially flat structures. Additionally, there is provided a conveyor device for the selective infeed or outfeed of the substantially flat structures which are to be wound-up or unwound, as the case may be, as well as a conveyor band arrangement arranged between the conveyor device and the winding core member. The conveyor band or belt arrangement serves to selectively infeed or outfeed, as the case may be, the substantially flat structures or products and the winding band or tape.
Such type of equipment is known, for instance, from Swiss Pat. No. 559,691, granted Jan. 31, 1975. With such equipment or apparatus, a further supply spool member and guide rolls for a second winding band are arranged above the stationarily arranged conveyor band arrangement which serves to infeed and outfeed, as the case may be, the substantially flat structures or products together with the winding band disposed therebelow. At the end of the conveyor band arrangement, the two winding bands or tapes, which are practically of the same width as the substantially flat structures, form a conveying gap in which the flat structures are fixedly clamped and delivered in so-called overfeed, together with the winding bands, to the driven winding core member and are wound thereupon in conjunction with the winding bands.
This solution is not only disadvantageous by virtue of the two winding bands or tapes which are required, but also for the reasons that there is limited the length of the conveying gap provided between the conveyor band arrangement and the winding core member or the package, as the case may be, and which conveying gap is only formed by both of the winding bands or tapes. In the event that the substantially flat structures are comparatively heavy, the danger exists that the lower winding band will sag at the region of the aforementioned conveying gap due to the unavoidable elongation thereof. Consequently, the upper winding band no longer remains in contact with the substantially flat structures Hence, at higher conveying velocities, these substantially flat structures are no longer adequately guided to ensure for an orderly winding-up or winding-off operation, as the case may be. It would be possible to somewhat ameliorate such drawback in that, in particular, the lower winding band would be placed under an appreciable tension or load which would reduce the tendency of sagging or hanging through. However, that would, in turn, require that during the wind-up of the flat structures, the drive of the winding core member, particularly in the case of increasing diameter of the wound package, would have to provide a rotational moment or torque which overcomes such tensional load, in other words, the drive would have to furnish an appreciably greater output for a given rotational speed.